For the production of an implant it is desirable not only to realize a maximum possible degree of automation in order to deliver high levels of efficiency, but also to achieve a best possible match to the individual characteristics of the anatomy of the patient in question, which in theory is at odds with a total automation of the manufacturing process. The desire for a patient-specific anatomical adaptation applies in this case to such different implants as bone implants, a spinal disk replacement or cartilage structures for plastic or reconstructive surgery.
Especially in the case of an implant which is subjected to a constant load due to an interaction, for example as a result of movements, with one or more neighboring tissue structures, a detailed patient-specific matching of the implant to the surrounding tissue can preclude a deterioration of the implant on account of the load. Equally, this also enables undesirable retroactive effects caused by the implant on the tissue structures involved in the interaction to be reduced, thus helping to prevent inflammations, abrasion, indurations and physical wear and tear reactions of the tissue structures as a consequence of the implant.
WO 2004/110309 discloses a method which, in order to produce an implant, firstly acquires three-dimensional tomographic image data of the region of the body for which the implant is intended and generates a manufacturing model of the implant on the basis of said image data of the body region. Finally, the implant is fabricated with the aid of the manufacturing model produced on the basis of the tomographic image data. In WO 2014/036551, a method for the patient-specific embodiment of an implant is disclosed which utilizes three-dimensional tomographic image data in particular for determining two-dimensional contact areas of a bone implant with the bone designated for the implant.
Generally in the case of the cited methods, however, the image data is acquired using a single modality only, i.e. for example via computed tomography (CT) or magnetic resonance tomography (MRT), and then a manufacturing model of the implant is created directly by way of said image data generated by one modality. The result of this is that, in the generation of the manufacturing model, essentially only those anatomical structures of the body region in question are taken into account which are particularly effectively resolved by the modality used, i.e. bone structures in CT or soft tissue structures in MRT.
The above-described challenges extend not only to implants, but also to other objects for use in the medical engineering field. The object can in particular be a positioning aid for radiation planning or for surgery.